In Forgetting Sarah Marshall, Thayer plays a woman on holiday with a new husband, played by Jack McBrayer. Thayer and McBrayer reunited on an episode of 30 Rock in which she portrays Kenneth Parcell's blind, shallow love interest. She also played Grace and Leo's daughter, Lila (at age 18), in the series finale of Will & Grace (2006). In 2009, she appeared in the film State of Play as Sonia Baker, the researcher and mistress of a congressman.